Update Revit File From Disk - Target Path

How can one specify a path location that is one or two folder before the project/ target path? 

This path would be the path to where the updated revit file, that has been stripped, will be saved too.

in short, the idea is to be able to update a revit file that is with in the main project folder but is not within the working directory, which seems to be the target directory as well, as a subfolder.

Thanks in advance